Savage Damsel and the Dwarf, The (Gerald Morris) - [Squire's Tales, The 03]

Her castle under siege by an evil knight who keeps beheading all her would-be rescuers, Lady Lynet sets out for help and finds assistance from an odd dwarf named Roger and a scruffy kitchen hand named Beaumains.
As the three unlikely companions return to Lynet’s castle, they face surprising adventures, including encounters with the uncanny Squire Terence, his master, Sir Gawain, and the majestic sorceress Morgan. And somewhere along the way, Lynet discovers that people can be much more than they seem.